I was really hoping that we wouldn't have to get in to the basic practical aspects of 'compressed air cleaning' by offering you a stick-a-nozzle-in-the-door-of-your-house example yet I obviously failed to consider the audience. Blowing stuff around, while it may be the only method available, is not cleaning anything. This especially becomes obvious when one cannot even see what they are cleaning, let alone effectively reach (at the proper angle) what needs to be (cough) 'cleaned'. Add in the abrasive particles trapped in one position or another when the drive stopped and you have but one thing: A half arse job done which many times exacerbates problems by blowing abrasive particles in to places that they would have never reached in the first place without your 'help'. I think that we are simply entering an age where people will believe everything and that if there is a video made about it...it must be the way to go. I say this as it is very hard for me to believe that "cleaning your house with an air hose" does not hit home somehow yet perhaps I need to find a video... ...run it !!!